A refrigeration apparatus including a refrigerant circuit in which intermediate-pressure gas refrigerant is injected into a compressor has been conventionally known, and is described in, for example, PATENT DOCUMENT 1. Specifically, the refrigerant circuit of the refrigeration apparatus includes a compressor, a heat-source-side heat exchanger, a first expansion valve, a gas-liquid separator, a second expansion valve, and a utilization-side heat exchanger sequentially connected together, and performs a two-stage expansion refrigeration cycle. The refrigerant circuit includes an injection pipe through which intermediate-pressure gas refrigerant in the gas-liquid separator is injected into the compressor. In the refrigeration apparatus, intermediate-pressure gas refrigerant is injected into the compressor to increase the amount of refrigerant circulating through the utilization-side heat exchanger during heating operation, thereby increasing the space heating capacity. This increases the coefficient of performance (COP) during heating operation, and enables energy efficient heating operation.